The fact that an albuminuric retinitis, occurring in the course of a chronic nephritis, is a sign of the gravest prognostic import, has long been recognized. Within the last five years, this has been the subject of considerable investigation, especially by the French clinicians, and several very interesting theories have been advanced. Chauffard1 attempted to explain albuminuric retinitis on the grounds of a hypercholesterinemia, while Onfrey and Balavoine2 attempted to show that changes in the viscosity of the blood played an important part. The theory that attracted the greatest amount of attention, however, was that advanced by Wida3 in 1910. He stated that albuminuric retinitis was the result of the retention in the blood of urea, or of some nitrogenous body closely allied to urea. In 1912 Widal4 reviewed the work of Chauffard and agreed with him that cholesterin, lipoids, and lecithin compounds might